Property, Equipment and Software, Net - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	[1]			$ 13,144,000	$ 30,916,000
Property, Equipment and Software
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense		$ 9,900,000	$ 11,600,000	20,100,000	23,400,000
Leasehold Improvements And Furniture And Fixtures
Property, Plant and Equipment [Line Items]
Impairment expense		0	1,500,000	0	1,500,000
Internally Developed Software
Property, Plant and Equipment [Line Items]
Impairment expense		$ 300,000	$ 4,300,000	$ 600,000	$ 4,500,000

[1] Prior period amounts have been reclassified to conform to the current period presentation. See “Notes to Condensed Consolidated Financial Statements – Note 1. Summary of Significant Accounting Policies” for additional information.